A group of environmentalists will be petitioning Prime Minister Narendra Modi, who is taking keen interest in cleaning of Ganga, to pursue with UNESCO for declaration of upper region of the holy river as a World Heritage Site.

"I have already written to the Union Ministry for Water Resources and now we will petition the PM to pursue the case. I will write a letter to the PM in this regard," reported to reporter quoting noted environmentalist Ranjit Bhargava.

This is important as the PM is himself keen on Ganga river conservation, he said.

Bhargava, who has been associated with Ganga cleaning campaign for the last 20 years and is a Padma Shri awardee, said he had already written to the PMO last year in this regard.

"In my letter, I said that unless there is a fully empowered agency to clean the Ganga, directly under the PMO assisted by Ministry of Ganga Rejuvenation, it will not do any good," he said.

The Narendra Modi government had last year launched the 'Swachh Ganga' campaign to clean the holy river.

Bhargava said he suggested that a well structured Territorial Army Division, consisting of Eco Task Force Units of ex-servicemen, should be set up to clean and rejuvenate the Ganga.

"Some measures have been taken, but a key suggestion that is yet to materialise is that powers to take action against deaulters must be absolute and concentrated in the hands of task force unit with a final appeal only to the Green Bench of the Supreme Court," he said.

Bhargava said he wrote to Union Minister for Water Resource Uma Bharti on the issue of World Heritage site status for Upper Ganga region from Gaumukh to Haridwar in Uttarakhand.

"But in response Minister of State for Water Resources Sanwar Lal Jat said the proposal has to be steered by Utrakhand government," he said.

"I suggested that keeping in mind Modi's deep passion for ensuring Ganga her due, his senior minister Uma Bharti may apprise the PM," he said.

Bhargava said now he has decided to take the issue directly to the doors of the PM.

"We want that PM should directly take initiative in this regard. Ganga river is revered by crores of people in India and the issue is not related to one particular state. It should be ensured that the river is restored to its pristine glory, made clean and pollution free. Even the apex court has expressed concern over the issue," he said.